As of: 2026-10-16 12:39 CEST.
Researched and written by AI agents (Claude Opus 5.5 in Claude Code), with a human editor. How we work: https://postcutoff.com/about/
Canonical page: https://postcutoff.com/m/flux-3-image-klein/

# FLUX 3 Image Klein

Black Forest Labs, FLUX 3 family. Status: current. Type: image generation. Released: 2026-10-15.

## How to call it

| Provider | Model id | Endpoint | Docs |
|---|---|---|---|
| BFL API | `flux-3-image-klein` |  | https://docs.bfl.ai/quick_start/pricing |
| Hugging Face |  |  | https://huggingface.co/black-forest-labs/flux-3-image-klein |
| GitHub (reference code) |  |  | https://github.com/black-forest-labs/flux-3-image-klein |

## Pricing

- Per image: $0.009
- Unit as published: per 1K image ($0.008 at 768², $0.011 at 1.5K, $0.014 at 2K, $0.036 at 4K; generation and editing priced the same)
- Source: https://docs.bfl.ai/quick_start/pricing
- Last checked: 2026-10-16

## Specs

- Input: text, image
- Output: image
- Context window: not published
- Max output: not published
- Open weights: yes
- Licence: FLUX Kommunity License v1.0 (free commercial use under US$5M annual revenue)

## Where it stands

- No newer image generation model in the registry yet.
- Before it from Black Forest Labs: FLUX.2 [klein] (4B / 9B) (2026-01-14) https://postcutoff.com/m/flux-2-klein/
- Weights are public. Licence: FLUX Kommunity License v1.0. See the licence for commercial terms.

## What stands out

- Open-weights 4K generation with bounding boxes: 5.6B model with FLUX 3 Image's native 4K output and 0–1000-grid bounding boxes to place, move, recolor, replace or remove elements; up to 10 reference images. Source: https://bfl.ai/blog/flux-3-image-klein
- Consumer-GPU builds: Distilled INT8 build runs on 8 GB VRAM; ~4 s per 1 MP on an RTX 5090, under 9 s on an RTX 4070 (BFL figures, ComfyUI). Source: https://bfl.ai/blog/flux-3-image-klein

## Notes

Base (50 steps, guidance 3.5) and distilled (16 steps) checkpoints; FP8/INT8/NVFP4. Needs the 9B prompt upsampler flux-3-image-klein-pup per the model card. Text encoder Qwen3-VL-4B-Instruct. HF access gated. Quality claims are BFL's internal Elo tests.

Small open-weights FLUX 3 model for local generation and editing.

Local: `diffusers` with `black-forest-labs/flux-3-image-klein` (accept the gate on Hugging Face first) and the prompt upsampler.

Sources: https://bfl.ai/blog/flux-3-image-klein , https://huggingface.co/black-forest-labs/flux-3-image-klein , https://docs.bfl.ai/quick_start/pricing

Model page: https://postcutoff.com/m/flux-3-image-klein/